1. Methods of Evolution
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ON YOUR OWN PAPER

2. Genetics
Genes hold the blueprint for all the different adaptations that animals have.
All the genes in one population are called the GENE POOL.
Each gene (such as eye color) has multiple alleles or options (blue, green, brown, etc.)
ALLELE FREQUENCY is a measure of how common an allele is in a population.
Blue Eyes
Green Eyes
Brown Eyes
Other

3. How does the gene pool change?
The gene pool can change from DNA MUTATIONS (introduce a new trait), MIGRATION, ENVIRONMENTAL CHANGE, or ISOLATION.
The movement of alleles from one population to another is called GENE FLOW.

4. MIGRATION
The FOUNDER EFFECT – a small number of individuals move to a new area

5. ENVIRONMENTAL CHANGE
The BOTTLENECK EFFECT – once a population has been greatly reduced in size, the few survivors have less genetic diversity

6. ISOLATION
Geographic isolation – when a river, mountain or other feature separates a population into two or more groups

7. ISOLATION
Temporal isolation – reproductive periods differ when the population (some mate in spring, others mate in fall)

8. ISOLATION
Behavioral isolation – isolation created by differences in courtship and mating behaviors.
Sexual selection – a trait increases mating success

9. ISOLATION
Reproductive isolation – isolation created by differences mating structures or ability to produce viable offspring

10. How organisms evolve
Convergent evolution – two unrelated species evolve similar characteristics (wings in birds and bats)

11. How organisms evolve
Divergent evolution – two related species evolve in different directions (like arm bones in mammals)

12. How organisms evolve
Coevolution – two or more species evolve in response to changes in each other (bird beak and flowers)